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A089873 Number of fixed points in range [A014137(n-1)..A014138(n-1)] of permutation A071665/A071666. 0
1, 1, 2, 2, 2, 4, 4, 4, 10, 6, 10, 12, 16, 20, 36, 28, 56, 46, 104, 84, 166 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

The number of n-node binary trees fixed by the corresponding automorphism(s).

LINKS

Table of n, a(n) for n=0..20.

A. Karttunen, C-program for computing the initial terms of this sequence

CROSSREFS

Sequence in context: A180019 A112801 A173862 * A096323 A035682 A054543

Adjacent sequences:  A089870 A089871 A089872 * A089874 A089875 A089876

KEYWORD

nonn

AUTHOR

Antti Karttunen, Nov 29 2003

STATUS

approved

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Last modified April 17 03:33 EDT 2014. Contains 240628 sequences.